Coming home

September 27, 2012

Two polar bears rest on an ice floe in the Arctic Ocean. (Photo by Julienne Stroeve)

I was sad to leave the ice pack. On our way out, the large swells made for a special treat as the ice-covered ocean pulsed with the waves. I tried to capture it on video, but since the boat was also moving up and down, it’s hard to capture the scale of the movement. Naturally, once we left the ice, I was once again sea sick, though not like I was the first time out. This time it was a more general malaise. I slept a lot the first day back into the open ocean, lulled to sleep by the motion. But happily I was able to eat so overall felt much better. Spent more time on the deck outside, getting fresh air.

We arrived in Svalbard on the 17th of September. We could see the islands off in the distance for several hours, and I spent hours on deck watching Svalbard get closer and admiring the views of the snow-capped mountains and glaciers. Longyearbyen was our final stopping point. It was great to step foot back on solid ground that evening, and we spent a few hours at the 5 or so pubs in Longyearbyen. The next day I tried to go for a hike with a couple of folks from the boat, but since we didn’t have a gun, we were advised not to leave the city limits. The hill outside of town that we were hoping to climb to had a fatality last year by a polar bear, so we wisely turned around and walked around the town instead. Would love to come back to Svalbard though and do some hiking and camping. I admire the folks though that live there year around, winter is long and dark there.

Looking back it was an amazing experience. It’s always great to have a chance to see in person what you’re studying. So much of my time is spent in front of the computer analyzing satellite data. It gives me a new perspective. I will be looking into more detail as to why the satellite data was suggesting there would be quite a bit more ice than I saw out there. The Arctic Ocean recorded the least amount of September ice this summer, at least since 1953 when we have reliable observations. The thin, first-year ice we mostly encountered is certainly behind the continued ice loss each year. As the Arctic loses more of its store of old, thick ice, that is replaced by thinner, first-year ice, summers like this will become the norm.

Climate models all suggest that the Arctic will eventually be open water in summer as the planet continues to warm from increases in greenhouse gases. The dates as to when this will happen are continually being revived in the models, with the models now saying sometime around 2050. Yet the ice loss we’re seeing today is still happening faster than many of the models can capture. So perhaps the Arctic will become ice free during summers even sooner. It’s hard to imagine that animals like the polar bears can adapt to such quick changes in their environment. I felt lucky to see as many bears as I did (6 total). I can’t imagine an Arctic without ice and bears.

I hope that doesn’t come to pass.

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5 comments

I’ve really enjoyed your eyewitness accounts of what’s going on up there in the frigid (but not nearly as much as it used to be) north. Satellites and models giving us the status of ice extent, area, and volume are one thing; a human actually sailing through the waters is something else entirely–especially when that human can write so descriptively. The smaller picture that verifies the big picture, perhaps?

Thanks for giving us warm-climate landlubbers a chance to tag along for part of the voyage…

…somewhere where it would come to the attention of at least one of the scientists quoted. This seemed like a good place.

Snow cover, melt ponds and ice thickness.

Ice floats so that only 1/9 of its mass is freeboard.

Settled snow has about 1/3 of the density of water/ice.

Take a slab of sea ice 80cm thick. Cover with 30cm of snow. The top surface of the ice is now at precisely the same height as the seawater it’s floating in. 30cm of snow has the mass of the 10cm of ice that would be supported above the surface by a submerged 80cm of ice..

Make that snow cover 40cm thick, and the top surface of the ice is actually submerged.

That’s an extreme case, and possibly too extreme to be relevent. Make the sea ice 80cm thick again. Cover with 20cm of snow. The ice surface is now proud of the sea, but only just. It is much easier, at the edges of the floe, for waves or swell to splash seawater onto the top of the ice, below the snow layer, which is permeable to water.

Given that any floe with melt ponds upon it must, by definition, hold some concavities, it is likely that some of this splashed seawater will not run back into the sea, but into the centre of the floe, adding to any meltponds, and replenishing them with water that it both briny and above the freezing/melting point.

Whether or not it is actually happening could be ascertained by taking salinity measurements of the meltponds.

Summary: snow cover facilitates the lateral incursion of seawater onto the top surface of an ice floe. As the ice gets thinner, and atmospheric moisture is increasing in the Arctic, leading to increased snowfall, this may become an increasing relevent factor.

(If all of this is well researched and understood, please forgive me for wasting your time, but it is not apparent from the article above).